Logarithmic functions have the following general properties
If y = log_{a} x, a > 0 and a ≠1, then
The domain of the function is the set of all positive real numbers and the range is the set of all real numbers.
For base a > 1, the function is increasing and concave and for 0 < a < 1, the function is decreasing and convex.
For all bases, y = 0, if x = 1